The actress joined Denzel Washington, Paul Mescal and Eddie Redmayne on last Friday's 'Graham Norton Show,' where Ronan sat quietly at first listening to the men chatting.

In particular, Redmayne was discussing how he prepped for his physically demanding role as an assassin in the TV miniseries, "The Day of the Jackal."

Redmayne explained that he learned how to use a cell phone as a weapon if a nemesis attacked him in one of the scenes.

This prompted Mescal and Norton — the show's host — to crack jokes about pulling out a phone to defend themselves in the face of a violent assault.

In fact, Norton did an impression mocking a person doing just that, while pointing at a fictitious assailant and asking, "Can you hold on a second?"

Redmayne agreed that a cell phone was not a proper mode of defense, causing Ronan to suddenly jump into the convo.

Ronan said, "That’s what girls have to think about all the time," before asking the women in the crowd, "Am I right, ladies?"

The audience erupted in loud applause as the men on the panel were left totally speechless.